Greetings,
I'm having trouble in a few scenes with characters of two or three different nationalities speaking in their native languages. Obviously, the usual method is to place the speech in <angle brackets> and a star (*) footnote with "*Translated from x" "**Translated from y" and so on. But, there are a couple of later scenes wherein I return to those same characters and it is not clear if they have switched languages, as some of them are multilingual.

So, two questions:

1.) In your opinion, is it customary to place a star (*) footnote every single time we open a new scene with a character that isn't speaking English, or is the first time I introduce them enough, as the reader will undoubtedly remember that they don't speak English?

2.) What about the fact that some of the characters may be switching languages, even mid-conversation? Is it enough to allow the reader to infer from context clues in the dialogue?

If you're going to have a character speaking Spanish all the way through, then I think it's enough to footnote it the first time, then you don't have to footnote it every page... but if you have a character that switches languages, and could be speaking something else in any given page or panel... then I think you're going to have to footnote each page or how would the readers know?